Merge Linus master into drm-next

The merge is clean, but the arm build fails afterwards,
due to API changes in the regulator tree.

I've included the patch into the merge to fix the build.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 61 insertions, 4 deletions

diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt
index d85fbae..c21c131 100644
--- a/Documentation/gpio/consumer.txt
+++ b/Documentation/gpio/consumer.txt
@@ -58,7 +58,6 @@ pattern where a GPIO is optional, the gpiod_get_optional() and
 gpiod_get_index_optional() functions can be used. These functions return NULL
 instead of -ENOENT if no GPIO has been assigned to the requested function:
 
-
 	struct gpio_desc *gpiod_get_optional(struct device *dev,
 					     const char *con_id,
 					     enum gpiod_flags flags)
@@ -68,6 +67,27 @@ instead of -ENOENT if no GPIO has been assigned to the requested function:
 						   unsigned int index,
 						   enum gpiod_flags flags)
 
+For a function using multiple GPIOs all of those can be obtained with one call:
+
+	struct gpio_descs *gpiod_get_array(struct device *dev,
+					   const char *con_id,
+					   enum gpiod_flags flags)
+
+This function returns a struct gpio_descs which contains an array of
+descriptors:
+
+	struct gpio_descs {
+		unsigned int ndescs;
+		struct gpio_desc *desc[];
+	}
+
+The following function returns NULL instead of -ENOENT if no GPIOs have been
+assigned to the requested function:
+
+	struct gpio_descs *gpiod_get_array_optional(struct device *dev,
+						    const char *con_id,
+						    enum gpiod_flags flags)
+
 Device-managed variants of these functions are also defined:
 
 	struct gpio_desc *devm_gpiod_get(struct device *dev, const char *con_id,
@@ -82,20 +102,37 @@ Device-managed variants of these functions are also defined:
 						  const char *con_id,
 						  enum gpiod_flags flags)
 
-	struct gpio_desc * devm_gpiod_get_index_optional(struct device *dev,
+	struct gpio_desc *devm_gpiod_get_index_optional(struct device *dev,
 							const char *con_id,
 							unsigned int index,
 							enum gpiod_flags flags)
 
+	struct gpio_descs *devm_gpiod_get_array(struct device *dev,
+						const char *con_id,
+						enum gpiod_flags flags)
+
+	struct gpio_descs *devm_gpiod_get_array_optional(struct device *dev,
+							 const char *con_id,
+							 enum gpiod_flags flags)
+
 A GPIO descriptor can be disposed of using the gpiod_put() function:
 
 	void gpiod_put(struct gpio_desc *desc)
 
-It is strictly forbidden to use a descriptor after calling this function. The
-device-managed variant is, unsurprisingly:
+For an array of GPIOs this function can be used:
+
+	void gpiod_put_array(struct gpio_descs *descs)
+
+It is strictly forbidden to use a descriptor after calling these functions.
+It is also not allowed to individually release descriptors (using gpiod_put())
+from an array acquired with gpiod_get_array().
+
+The device-managed variants are, unsurprisingly:
 
 	void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
 
+	void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
+
 
 Using GPIOs
 ===========
@@ -222,6 +259,26 @@ GPIOs belonging to the same bank or chip simultaneously if supported by the
 corresponding chip driver. In that case a significantly improved performance
 can be expected. If simultaneous setting is not possible the GPIOs will be set
 sequentially.
+
+The gpiod_set_array() functions take three arguments:
+	* array_size	- the number of array elements
+	* desc_array	- an array of GPIO descriptors
+	* value_array	- an array of values to assign to the GPIOs
+
+The descriptor array can be obtained using the gpiod_get_array() function
+or one of its variants. If the group of descriptors returned by that function
+matches the desired group of GPIOs, those GPIOs can be set by simply using
+the struct gpio_descs returned by gpiod_get_array():
+
+	struct gpio_descs *my_gpio_descs = gpiod_get_array(...);
+	gpiod_set_array(my_gpio_descs->ndescs, my_gpio_descs->desc,
+			my_gpio_values);
+
+It is also possible to set a completely arbitrary array of descriptors. The
+descriptors may be obtained using any combination of gpiod_get() and
+gpiod_get_array(). Afterwards the array of descriptors has to be setup
+manually before it can be used with gpiod_set_array().
+
 Note that for optimal performance GPIOs belonging to the same chip should be
 contiguous within the array of descriptors.